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Risk factors for retinal detachment include severe myopia, retinal tears, trauma, family history, as well as complications from cataract surgery.
Retinal detachment can be mitigated in some cases when the warning signs are caught early. The most effective means of prevention and risk reduction is through education of the initial signs, and encouragement for people to seek ophthalmic medical attention if they have symptoms suggestive of a posterior vitreous detachment. Early examination allows detection of retinal tears which can be treated with laser or cryotherapy. This reduces the risk of retinal detachment in those who have tears from around 1:3 to 1:20. For this reason, the governing bodies in some sports require regular eye examination.
Trauma-related cases of retinal detachment can occur in high-impact sports or in high speed sports. Although some recommend avoiding activities that increase pressure in the eye, including diving and skydiving, there is little evidence to support this recommendation, especially in the general population. Nevertheless, ophthalmologists generally advise people with high degrees of myopia to try to avoid exposure to activities that have the potential for trauma, increase pressure on or within the eye itself, or include rapid acceleration and deceleration, such as bungee jumping or roller coaster rides.
Intraocular pressure spikes occur during any activity accompanied by the Valsalva maneuver, including weightlifting. An epidemiological study suggests that heavy manual lifting at work may be associated with increased risk of rhegmatogenous retinal detachment, but this relationship is not strong. In this study, obesity also appeared to increase the risk of retinal detachment. A high Body Mass Index (BMI) and elevated blood pressure have been identified as a risk factor in non-myopic individuals.
Genetic factors promoting local inflammation and photoreceptor degeneration may also be involved in the development of the disease.
Other risk factors include the following:
- Glaucoma
- AIDS
- Cataract surgery
- Diabetic retinopathy
- Eclampsia
- Family history of retinal detachment
- Homocysteinuria
- Malignant hypertension
- Metastatic cancer, which spreads to the eye (eye cancer)
- Retinoblastoma
- Severe myopia
- Smoking and passive smoking
- Stickler syndrome
- Von Hippel-Lindau disease
In general, approximately one-third of congenital cataracts are a component of a more extensive syndrome or disease (e.g., cataract resulting from congenital rubella syndrome), one-third occur as an isolated inherited trait, and one-third result from undetermined causes. Metabolic diseases tend to be more commonly associated with bilateral cataracts.
It has been suggested that the disease follows a x-linked pattern of inheritance though studies done on this particular disease are few.
Most people with the disease need laser repairs to the retina, and about 60 per cent need further surgery.
The cause of this condition is not presently known. It appears to be inherited in an autosomal dominant fashion.
Low vitamin C intake and serum levels have been associated with greater cataract rates. However, use of supplements of vitamin C has not demonstrated benefit.
Zonular cataract and nystagmus, also referred as Nystagmus with congenital zonular cataract is a rare congenital disease associated with Nystagmus and zonular cataract of the eye.
Cigarette smoking has been shown to double the rate of nuclear sclerotic cataracts and triple the rate of posterior subcapsular cataracts. Evidence is conflicting over the effect of alcohol. Some surveys have shown a link, but others which followed people over longer terms have not.
Approximately 50% of all congenital cataract cases may have a genetic cause which is quite heterogeneous. It is known that different mutations in the same gene can cause similar cataract patterns, while the highly variable morphologies of cataracts within some families suggest that the same mutation in a single gene can lead to different phenotypes. More than 25 loci and genes on different chromosomes have been associated with congenital cataract. Mutations in distinct genes, which encode the main cytoplasmic proteins of human lens, have been associated with cataracts of various morphologies, including genes encoding crystallins (CRYA, CRYB, and CRYG), lens specific connexins (Cx43, Cx46, and Cx50), major intrinsic protein (MIP) or Aquaporin, cytoskeletal structural proteins, paired-like homeodomain transcription factor 3 (PITX3), avian musculoaponeurotic fibrosarcoma (MAF), and heat shock transcription factor 4 (HSF4).
Acorea or fibrous occlusion of the pupil, microphthalmia and cataracts are present in both eyes. Microcornea and iridocorneal dysgenesis also occur. The retina and optic disc are normal.
Aniridia is the absence of the iris, usually involving both eyes. It can be congenital or caused by a penetrant injury. Isolated aniridia is a congenital disorder which is not limited to a defect in iris development, but is a panocular condition with macular and optic nerve hypoplasia, cataract, and corneal changes. Vision may be severely compromised and the disorder is frequently associated with a number of ocular complications: nystagmus, amblyopia, buphthalmos, and cataract. Aniridia in some individuals occurs as part of a syndrome, such as WAGR syndrome (kidney nephroblastoma (Wilms tumour), genitourinary anomalies and intellectual disability), or Gillespie syndrome (cerebellar ataxia).
Irvine–Gass syndrome, pseudophakic cystoid macular edema or postcataract CME is one of the most common causes of visual loss after cataract surgery. The syndrome is named in honor of S. Rodman Irvine and J. Donald M. Gass.
The incidence is more common in older types of cataract surgery, where postcataract CME could occur in 20–60% of patients, but with modern cataract surgery, incidence of Irvine–Gass syndrome have reduced significantly.
Replacement of the lens as treatment for cataract can cause pseudophakic macular edema. (‘pseudophakia’ means ‘replacement lens’) this could occur as the surgery involved sometimes irritates the retina (and other parts of the eye) causing the capillaries in the retina to dilate and leak fluid into the retina. This is less common today with modern lens replacement techniques
Aniridia may be broadly divided into hereditary and sporadic forms. Hereditary aniridia is usually transmitted in an autosomal dominant manner (each offspring has a 50% chance of being affected), although rare autosomal recessive forms (such as Gillespie syndrome) have also been reported. Sporadic aniridia mutations may affect the WT1 region adjacent to the AN2 aniridia region, causing a kidney cancer called nephroblastoma (Wilms tumor). These patients often also have genitourinary abnormalities and intellectual disability (WAGR syndrome).
Several different mutations may affect the PAX6 gene. Some mutations appear to inhibit gene function more than others, with subsequent variability in the severity of the disease. Thus, some aniridic individuals are only missing a relatively small amount of iris, do not have foveal hypoplasia, and retain relatively normal vision. Presumably, the genetic defect in these individuals causes less "heterozygous insufficiency," meaning they retain enough gene function to yield a milder phenotype.
- AN
- Aniridia and absent patella
- Aniridia, microcornea, and spontaneously reabsorbed cataract
- Aniridia, cerebellar ataxia, and mental deficiency (Gillespie syndrome)
Wagner's syndrome has for a long time been considered a synonym for Stickler's syndrome. However, since the gene that is responsible for Wagner disease (and Erosive Vitreoretinopathie) is known (2005), the confusion has ended. For Wagner disease is the Versican gene (VCAN) located at 5q14.3 is responsible.
For Stickler there are 4 genes are known to cause this syndrome: COL2A1 (75% of Stickler cases), COL11A1 (also Marshall syndrome), COL11A2 (non-ocular Stickler) and COL9A1 (recessive Stickler).
The gene involved helps regulate how the body makes collagen, a sort of chemical glue that holds tissues together in many parts of the body. This particular collagen gene only becomes active in the jelly-like material that fills the eyeball; in Wagner's disease this "vitreous" jelly grabs too tightly to the already weak retina and pulls it away.
Intraoperative floppy iris syndrome (IFIS) is a complication that may occur during cataract extraction in certain patients. This syndrome is characterized by a flaccid iris which billows in response to ordinary intraocular fluid currents, a propensity for this floppy iris to prolapse towards the area of cataract extraction during surgery, and progressive intraoperative pupil constriction despite standard procedures to prevent this.
IFIS has been associated with tamsulosin (e.g., Flomax), a medication widely prescribed for urinary symptoms associated with benign prostatic hyperplasia (BPH). Tamsulosin is a selective alpha blocker that works by relaxing the bladder and prostatic smooth muscle. As such, it also relaxes the iris dilator muscle by binding to its postsynaptic nerve endings. Even if a patient has only taken tamsulosin once in their life, that dose is enough to cause IFIS during cataract extraction indefinitely. Various alpha-blockers are associated with IFIS, but tamsulosin has a stronger association than the others.
A joint statement of two ophthalmologic societies states that "the other major class of drugs to treat BPH — 5-alpha reductase inhibitors — do not appear to cause IFIS to any significant degree." 5-ARIs include finasteride, a medication typically used as first line therapy for BPH and androgenic alopecia. The medication is also associated with cataract formation.
IFIS may also be associated with other causes of small pupil like synechiae, pseudoexfoliation and other medications (used for conditions such as glaucoma, diabetes and high blood pressure). IFIS does not usually cause significant changes in postoperative outcomes. Patients may experience more pain, a longer recovery period, and less improvement in visual acuity than a patient with an uncomplicated cataract removal.
The severity of the condition is not linked to the duration of tamsulosin intake.
The cataract-microcornea syndrome is the association of congenital cataract and microcornea.
This ocular pathology was first described by Iwanoff in 1865, and it has been shown to occur in about 7% of the population. It can occur more frequently in the older population with postmortem studies showing it in 2% of those aged 50 years and 20% in those aged 75 years.
Persistent tunica vasculosa lentis is a congenital ocular anomaly. It is a form of persistent hyperplastic primary vitreous (PHPV).
It is a developmental disorder of the vitreous. It is usually unilateral and first noticed in the neonatal period. It may be associated with micropthalmos, cataracts, and increased intraocular pressure. Elongated ciliary processes are visible through the dilated pupil. A USG B-scan confirms diagnosis in the presence of a cataract.
There is no known cure for this syndrome. Patients usually need ophthalmic surgery and may also need dental surgery
Genetic counseling and screening of the mother's relatives is recommended.
According to recent research not a single theory is able to explain the cause fully. However current plausible theories include infection with "Toxoplasma gondii", Herpes simplex virus, Rubella, neurogenic causes, and autoimmune pathology.
The incidence of retinal detachment in otherwise normal eyes is around 5 new cases in 100,000 persons per year. Detachment is more frequent in middle-aged or elderly populations, with rates of around 20 in 100,000 per year. The lifetime risk in normal individuals is about 1 in 300. Asymptomatic retinal breaks are present in about 6% of eyes in both clinical and autopsy studies.
- Retinal detachment is more common in people with severe myopia (above 5–6 diopters), in whom the retina is more thinly stretched. In such patients, lifetime risk rises to 1 in 20. About two-thirds of cases of retinal detachment occur in myopics. Myopic retinal detachment patients tend to be younger than non-myopic ones.
- Retinal detachment is more frequent after surgery for cataracts. The estimated long-term prevalence of retinal detachment after cataract surgery is in the range of 5 to 16 per 1000 cataract operations, but is much higher in patients who are highly myopic, with a prevalence of up to 7% being reported in one study. One study found that the probability of experiencing retinal detachment within 10 years of cataract surgery may be about 5 times higher than in the absence of treatment.
- Tractional retinal detachments can also occur in patients with proliferative diabetic retinopathy or those with proliferative retinopathy of sickle cell disease. In proliferative retinopathy, abnormal blood vessels (neovascularization) grow within the retina and extend into the vitreous. In advanced disease, the vessels can pull the retina away from the back wall of the eye, leading to tractional retinal detachment.
Although retinal detachment usually occurs in just one eye, there is a 15% chance of it developing in the other eye, and this risk increases to 25–30% in patients who have had a retinal detachment and cataracts extracted from both eyes.
This syndrome is due to mutations in the Nance Horan gene (NHS) which is located on the short arm of the X chromosome (Xp22.13).
Lenticonus (/len·ti·co·nus/ (len″tĭ-ko´nus)) [lens + L. conus, cone] is a rare congenital anomaly of the eye characterized by a conical protrusion on the crystalline lens capsule and the underlying cortex. It can reach a diameter of 2 to 7 mm. The conus may occur anteriorly or posteriorly. If the bulging is spherical, instead of conical, the condition is referred to as "lentiglobus". It produces a decrease in visual acuity and irregular refraction that cannot be corrected by either spectacle or contact lenses.
Biomicroscopically "lenticonus" is characterized by a transparent, localized, sharply demarcated conical projection of the lens capsule and cortex, usually axial in localization. In an early stage, retro-illumination shows an «oil droplet» configuration. Using a narrow slit, the image of a conus is observed. In a more advanced stage associated subcapsular and cortical opacities appear. Retinoscopically the oil droplet produces a pathognomonic scissors movement of the light reflex. This phenomenon is due to the different refraction in the central and the peripheral area of the lens. Ultrasonography also can illustrate the existence of a "lenticonus". A-scan ultrasonography may reveal an increased lens thickness and B- scanultrasonography may show herniated lenticular material, suggestive of a lenticonus. Amblyopia, cataract, strabismus and loss of central fixation may be observed in association with lenticonus posterior. Cataract, flecked retinopathy, posterior polymorphous dystrophy and corneal arcus juvenilis may be encountered in association with lenticonus anterior that occurs as a part of the Alport syndrome.
Exist two distinct types of "lenticonus" based on the face of the lens affected.
There is no good evidence for any preventive actions, since it appears this is a natural response to aging changes in the vitreous. Posterior vitreous detachment (PVD) has been estimated to occur in over 75 per cent of the population over age 65, that PVD is essentially a harmless condition (although with some disturbing symptoms), and that it does not normally threaten sight. However, since epiretinal membrane appears to be a protective response to PVD, where inflammation, exudative fluid, and scar tissue is formed, it is possible that NSAIDs may reduce the inflammation response. Usually there are flashing light experiences and the emergence of floaters in the eye that herald changes in the vitreous before the epiretinal membrane forms g
Childhood cataract is cataract that occurs at birth or in childhood. It may be congenital or acquired.